Face coverings, surgical masks, and face filtering piece (FFP) respirators: what’s the difference and how are they tested?

You’ll all have seen wide variety of masks and face coverings worn in a wide (and often alarming!) variety of ways. Leaving aside the (in)correct wearing of masks, it’s useful to see some comparative data on the relative respiratory protection offered by different mask materials. This study, published years ago (pre COVID!), does just that.

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Considering the role of environmental contamination in the spread of COVID-19

We know that respiratory viruses can be spread through droplets, occasionally aerosols, and contact routes (see Figure 1). But what is the relative importance of these transmission routes for the SARS-CoV-2 virus, which causes COVID-19? A new pre-print paper published yesterday provides evidence that the stability of the SARS-CoV-2 coronavirus is broadly comparable to the ‘original’ SARS coronavirus (SARS-CoV-1) on dry surfaces and in aerosols. This paper supports an important role for dry surface contamination and aerosols in the spread of SARS-CoV-2, and suggests that improved environmental persistence isn’t the key to the relative success of SARS-CoV-2 over SARS-CoV-1.

Figure 1: Transmission routes of respiratory viruses (from this review article).

covid transmission routes

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